The opera takes place between 1789 and 1794 in Paris and in the town of Compiègne in northeastern France, the site of the Carmelite nuns’ convent. Its historical basis is the martyrdom of a group of 16 Carmelite nuns and lay sisters from Compiègne, who chose to offer themselves as victims for the restoration of peace to France during the Revolution. Yannick Nézet-Séguin leads the classic John Dexter production of Poulenc’s devastating story of faith and martyrdom. Mezzo-soprano Isabel Leonard sings the touching role of Blanche and soprano Karita Mattila, a legend in her own time, returns to the Met as the Prioress.